Sewing machine triple feeder attachment for stitching elastic to cloth pieces



Jan. 3, 1967 BQSER ET AL 3,295,484

SEWING MACHINE TRIPLE FEEDER ATTACHMENT FOR STITCHING ELASTIC TO CLOTH PIECES 4 Sheets-$heet 1 Filed May 19, 1964 INVENTORS RONALD J. 3065/? ,EUGENE L. NESCHLER Jan. 3, 1967 R. J. BOSER ETAL 3,295,484 SEWING MACHINE TRIPLE FEEDER ATTACHMENT FOR STIT CHING ELASTIC TO CLOTH PIECES 4 Sheets-Sheet 2 Filed May 19, 1964 E 2 \W T INVENTORS RON/MD -J. BOSE]? L 'UGEIVE L NEQS'CHLER AfifiRNi fi.

Jan. 3, 1967 R. J. BOSER ET AL SEWING MACHINE TRIPLE FEEDER ATTACHMENT FOR STITCHING ELASTIC TO CLOTH PIECES Filed May 19, 1964 4 SheetsSheet 5 INVENTORS RON/1L0 J. B0567? QUGENE L. WESCHLER R. J. BOSER ET AL Jan. 3, 1967 SEWING MACHINE TRIPLE FEEDER ATTACHMENT FOR STITCHING ELASTIC TO CLOTH PIECES Filed May 19, 1964 4 SheetsSheet 4.

. I \\I lm w d, A J.L DE 00 6? Qw B United States Patent SEWING MACHINE TRIPLE FEEDER ATTACH- MENT FOR STITCHING ELASTIC T0 CLOTH PIECES Ronald J. Boser, 26179 Langston Ave., Glen ()akes, N.Y. 11004, and Eugene Weschler, 288 Bel-Air Drive, Massapequa,N.Y. 11762 Filed May 19, 1964, Ser. No. 368,473 3 Claims. (Cl. 112-458) This invention relates generally to sewing machines. More specifically, it relates to sewing machine pressure foot bars and associated feed dogs.

It is generally well known to those skilled in the art that it is quite impossible to sew a wrinkle-free seam when attaching an elastic tape or the like to an edge of non-stretchable fabric such as cotton, nylon, silk or the like. During the sewing together thereof, skill is required to feed an equal length of unstretched dissimilar materials between the pressure foot bar and feed dog of an ordinary sewing machine having a single pressure shoe. Nevertheless, the pressure of the foot bar stretches the elastic tape but not the cotton fabric and a certain amount of wrinkling is almost certain'to occur. Additionally, when a folded-over portion or otherwise thickened portion of either material is fed between the pressure foot bar and feed dog, the thickened portion sometimes gets caught or momentarily halted in the space between the feed dog tooth stub rows. These conditions are, of course, objectionable.

Accordingly, it is a principal object of the persent invention to provide a shoe assembly and associated feed dog having means to sew a wrinkle-free seam comprising an elastic and another elastic or non-stretchable fabric.

Another object of the present invention is to provide a shoe assembly and associated feed dog having self-contained means to prevent a thickened portion of material passing therebetween from becoming caught or halted therein during sewing operation.

Another object is to provide a shoe assembly having means to exert a plurality of pressures upon the work being sewn and wherein one of the pressures comprises a direct pressure from the foot bar exerted upon the nonstretchable or stretchable fabric and the other pressure comprises resilient pressure upon the elastic material. Thus, a firm heavy pressure is applied to the stretchable or non-stretchable material to insure steady feeding thereof under the needle and a resilient lesser pressure is applied to the elastic material so as to not stretch the same.

Still another object is to provide a feed dog associated with the shoe assembly having means for the work to feed in a constant straight singular direction.

A further object of the invention is to provide a multi-pressure shoe assembly and feed dog which are adaptable for producing a narrow throw zigzap stitch, or a wide throw fancy zigzag stitch.

Other objects are to produce a multi-pressure shoe assembly and feed dog which are simple in design, rugged in construction, easy to use and efiicient in operation.

For further comprehension of the invention, and of the objects and advantages thereof, reference will be had to the following description and accompanying drawings, and to the appended claims in which the various novel features of the invention are more particularly set forth.

In the accompanying drawings forming a material part of this disclosure:

FIG. 1 is a fragmentary front perspective view of a sewing machine shown incorporating the present invention therein and shown in operative use.

FIG. 1A is a fragmentary perspective view showing a modified seam being made therewith.

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FIG. 2 is a cross-sectional view taken on line 22 of FIG. 1.

FIG. 3 is a View of the shoe assembly taken on line 33 of FIG. 2.

FIG. 4' is a cross-sectional view taken on line 44 of FIG. 2.

FIG. 5 is a cross-sectional view taken on line 55 of FIG. 2.

FIG. 6 is a cross-sectional view taken on line 66 of FIG. 2.

FIG. 7 is an exploded perspective view of the parts comprising the shoe assembly.

FIG. 8 is a plan view of a feed dog and associated needle plate adapted for producing a narrow throw zigzag stitch.

FIG. 9 is a plan view of a feed dog and associated needle plate adapted for producing a wide throw fancy zigzag stitch.

FIG. 10 is a front elevational view of a sewing machine head incorpoarting the present invention and showing diagrammatically the drive mechanism for operation thereof. 7

FIG. 11 is a cross-sectional view taken on line 1111 of FIG. 10.

Referring now to the drawings in detail, the numeral 20 represents a multi-pressure shoe assembly and associated feed dog according to the present invention wherein there is a shoe assembly 21 and feed dog 22 projecting upwardly through a needle plate 23. The shoe assembly is attached to the lower end of a pressure foot bar 24 of a sewing machine head 25. Bar 24 moves vertically through a bore 10 in the machine head 25 and is formed with an axial recess 11 intersecting its top end in which is housed a coil spring 12. The upper end of the bore is internally screw threaded as indicated at 13. An enlarged screw member 14 is threaded into the threaded top end of the bore and is provided with a round rod extension 15 plugged into the axial recess 11 in the bar 24, the inner end of the extension 15 engaging the coil spring 12 in the recess. A knurled head 16 is formed on the top end of the screw member and the head is formed with a hub portion 17 and interposed between the hub portion and the top of the head 15 there is a compression spring 18. The shoe assembly is comprised of a left shoe 26 and a right shoe 27 supported on a block 28 attached to a shank 2? carried by the pressure foot bar.- The left shoe is provided with a transverse opening 30 to receive a pin 31. An open slot 32 in the left shoe receives a depending lug 33 on block 28, the lug having a transverse opening 34 to receive pin 31. Thus, the left shoe is carried pivotably free relative to the block.

The right shoe likewise has a transverse opening 35 to receive a pin 36 therethrough and have an open slot 37 to receive therein a plate 38 having transverse opening 39, the pin extending through the opening 39 to support the right shoe pivotally free relative to the plate. An upstanding post 40 is rigidly afiixed to the plate, the post extending upwardly and being slidably carried in a vertical opening 41 in block 28. The side of the post has a flat head 42 thereupon engageable with a pin 43 mounted in block 28 for purpose of limiting the post travel. A compression coil spring 44 is carried within opening 41, the lower end of the spring bearing against the upper end of the post while the upper end of the spring bears against a screw 45 threadedly mounted on block 28 and being vertically adjustable to vary the pressure against the plate. A lock nut 46 serves to rigidly secure the screw in a pro-selected position. The block has a pair of horizontal threaded openings 47 to receive screws 48 which pass through horizontal slots 49 in the shank. The slots allow lateral adjustment of the shoes relative to the pres- The feed dog 22 (shown in FIG. 8) comprises a fiat 7 plate 56 having upwardly projecting rows of teeth. Two of these rows of teeth, identified by the reference numeral 57, are in alignment with the lower surface of the left shoe, whereas the stub row 58 and row 59 are in alignment with the lower surface of the right shoe. The needle plate .23 has openings 60 therein to allow the teeth to project upwardly therethrough. A transverse slot 61 in the needle plate is provided for the needles travel therethrough at opposite ends of the slot. The above described feed dog is for a narrow throw zigzag stitch;

A feed dog 62 (shown in FIG. 9) is for wide throw fancy zigzag stitch and includes a plate 63 having two rows of teeth 64 which are in alignment with the left shoe and two double stub rows 65 which are in alignment with the right shoe. A space 66 is formed between the stubs in each row.

In operative use, a motor (not shown) drives pulley 70 by means of belt 71 causing main shaft 72 to rotate in the upright standard 25, bracket arm 26' and head 25.

tions may be made within the scope of the invention as.

defined in the appended claims.

Having thus described our invention, what we claim as new, and desire to secure by United States Letters Patent.

a head on the other end of the bracket arm, a needle bar carrying a needle supported on said arm, a feed dog within: said base, a pressure foot bar supported on said arm, said.

pressure foot bar carrying a shoe assembly at its lower end, said shoe assembly being in contact alignment on its lower side with the upper side of said feed dog, a drive mechanism carried within said head for providing vertical 1 reciprocal movement of said needle bar, mechanical means within said arm for providing lateral movement of the lower end of said needle bar, mechanism within said head for imparting a generally circular movement about a lat,

eral axis to said feed dog, means for applying a plurality I dog than the other, said pressure foot being vertically ad- Cam 73 mounted on the main shaft carries a lever 74 by A bevel gear 78 mounted on the main shaft drives bevel gear 79 having bevel gear 80 on the same axis which drives bevel gear 81 on cross shaft 82. A cam 83 mounted on the cross shaft imparts lateral movement to cam follower 84 and arm 85 carrying collar 86 through which the lower end of the needle bar freely slides. Thus, lateral movement is imparted to the needle 87 carried by the needle bar.

A cam 88 mounted on the main shaft drives earn follower 89 providing vertical movement to rod 90 which in turn vertically moves the end of horizontal bar 91 supported at its midpoint on fulcrum 92. This causes the opposite end of the bar 91 carrying the feed dog to move in opposite vertical direction.

Another cam 93 also mounted on the main shaft drives justable relative to said arm and being selectively urged by a compression coil between said arm and saidpressure foot bar to bear downward with a full pressure through one of said shoe elements and a resilient pressure through the other of said shoe elements, one of said shoe being afiixed pivotally free to said block by a transverse pin, said left shoe element thus transmitting the said full pressure of said pressure foot bar downward against said feed dog, said right shoe element being secured pivotally free by a transverse second pin to a plate, said plate a having an upstanding post, said block having vertical cam follower 94 providing vertical movementto rod 95 A attached at its lower end to angle lever 96 pivoted about pin 97. The angle lever has bifurcated ends 98 between which the rod 91 is held captive. Thus, vertical movement of rod 95 is transmitted by means of the angle lever to horizontal movement of the rod 91. Thus, vertical and horizontal movement is imparted to the feed dog to produce a combined conventional generally circular movement.

To sew a folded-over seam 99 or to attach an elastic tape 100 to a non-stretchable, fabric sheet 101, the operator feeds the tape from its guide 100 and the sheet 101 under both shoes wtih the folded portion or the elastic tape under the right shoe. Thus, firm pressure is delivered to the sheet by the left shoe whereas resilient, lighter pressure is delivered to the relatively thicker folded-over portion or elastic tape. The double row of teeth under the left shoe provides heavy firm pressure to prevent any thickened portion of work to become caught under the right shoe.

While we have illustrated and described the preferred embodiment of our invention,- it is to be understood that a opening to slidably receive said post, said post having an undercut portion on its aids and said block having a mounted pin adjacent thereto to prevent disengagement of said post from said block, a compression coil spring within said opening between the upper end of said post and a screw threadedly attached in the upper end of said opening, said screw being vertically adjustable for selective pressure against said post, and a lock nut threadedly en gaged on said screw.

2. In a sewing machine, the combination as set forth in claim 1, wherein said feed dog is comprised of a platev having a plurality of rows of upwardly extending teeth, a plurality of said rows of teeth being in contact alignment with said left shoe element, and a plurality of said rows of teeth being in contact alignment with said right shoe element.

3:. In a sewing machine, the combination as set forth in claim 2, wherein a needle plate is provided over said feed dog, said needle plate having a plurality of slots each of which receives one of said rows of teeth of said feed dog.

References Cited by the Examiner UNITED STATES PATENTS 1,521,701 1/1925 Motfatt 112-235 2,487,285 11/ 1949 Voight 112-235 2,611,333 9/1952 Ritter 112-235 3,005,429 10/ 1961 Weschler 112 -235 3,044,428 7/ 1962 Hale et a1. 112-235 3,051,107 8/1962 Johnson 112158 3,146,743 9/ 1964 Minehan 112-235 X PATRICK D. LAWSON, Primary Examiner.

1. In a sewing machine, a base, an upright standard. on the base, a bracket arm extending from said standard, 

1. IN A SEWING MACHINE, A BASE, AN UPRIGHT STANDARD ON THE BASE, A BRACKET ARM EXTENDING FROM SAID STANDARD, A HEAD ON THE OTHER END OF THE BRACKET ARM, A NEEDLE BAR CARRYING A NEEDLE SUPPORTED ON SAID ARM, A FEED DOG WITHIN SAID BASE, A PRESSURE FOOT BAR SUPPORTED ON SAID ARM, SAID PRESSURE FOOT BAR CARRYING A SHOE ASSEMBLY AT ITS LOWER END, SAID SHOE ASSEMBLY BEING IN CONTACT ALIGNMENT ON ITS LOWER SIDE WITH THE UPPER SIDE OF SAID FEED DOG, A DRIVE MECHANISM CARRIED WITHIN SAID HEAD FOR PROVIDING VERTICAL RECIPROCAL MOVEMENT OF SAID NEEDLE BAR, MECHANICAL MEANS WITHIN SAID ARM FOR PROVIDING LATERAL MOVEMENT OF THE LOWER END OF SAID NEEDLE BAR, MECHANISM WITHIN SAID HEAD FOR IMPARTING A GENERALLY CIRCULAR MOVEMENT ABOUT A LATERAL AXIS TO SAID FEED DOG, MEANS FOR APPLYING A PLURALITY OF DIFFERENT PRESSURES BY SAID SHOE ASSEMBLY AGAINST SAID FEED DOG, SAID SHOE ASSEMBLY BEING COMPRISED OF A PAIR OF LATERALLY ADJACENT SHOE ELEMENTS EACH OF WHICH HAS MEANS TO EXERT A DIFFERENT DOWNWARD PRESSURE AGAINST SAID FEED DOG THAN THE OTHER, SAID PRESSURE FOOT BEING VERTICALLY ADJUSTABLE RELATIVE TO SAID ARM AND BEING SELECTIVELY URGED BY A COMPRESSION COIL BETWEEN SAID ARM AND SAID PRESSURE FOOT BAR TO BEAR DOWNWARD WITH A FULL PRESSURE THROUGH ONE OF SAID SHOE ELEMENTS AND A RESILIENT PRESSURE 